Fire and Forge
by Aria6
Summary: AU! Inspired by the My Sweet Monster doujinshi. Emiya has been raised from birth to be a magus and succeeded in every way. He's powerful, rich and he has many enemies, inside his life and without. Enter Cu Chulainn, a brash beast man who stumbles onto trouble and doesn't care how dangerous it is. Emiya will make use of him, but will it become something more? Emiya/Cu Chulainn


_I knew from the moment I met him I would be crazy to trust him._

 _A Magus. A powerful, human magus, colder than the North winds and with a Crest engraved into both his arms and back. Skin an unnatural brown, not a tan but overuse of Reinforcement. Hair bleached white with magic. A warrior magus, he was my natural enemy._

 _But when he looked at me with golden eyes that were so strong, so forthright and somehow honest, I couldn't help but trust him. Because I sensed a deeper truth in my soul._

 _He might be a magus but he was far from a typical one._

* * *

"Pweh, this is getting fucking old!" Cu Chulainn spat as he tried – again – to kill a hydra. He had a flaming brand and was attempting to emulate Hercules and cut heads off before applying the brand. Easier said than done because he was no magus and there was a wind and the fucking brand kept _going out!_ "AUGH!" Again, the fucking brand went out! This was bullshit! Three of the hydras heads went for him and Cu swore as he tried to evade. If the fire was out he couldn't afford to lop them off, it would only make his situation worse.

Then something flashed in front of his face and Cu Chulainn blinked as a head fell off the main body and the stump was seared with magical fire?

"Fuuuuuck!" Cu Chulainn hissed as a man in black and gold began attacking the hydra. Cu Chulainn got out of the way and began trying to restart his brand, pulling out a lighter.

"Stop being a fool! My wand is more efficient, lop off heads for me!" …Uh… Cu Chulainn wasn't sure he wanted to trust this guy but couldn't deny the command made sense. Dropping the brand he gripped his spear with both hands. It'd be hella easier to take off heads this way anyway.

Diving into the fray, Cu Chulainn narrowly avoided a vicious set of teeth before slashing a head off, right where the jaw connected. It wasn't effortless but Gae Bolg was up for it and after a hard impact, the head flew away in a spray of blood. Then a gout of fire went over his shoulder – a bit too fucking close! – and cauterized the head. The hydra's remaining heads wailed, trying to get at him and the man at the same time. They were uncoordinated though, fighting poorly with two targets. This was… way easier…

Cu Chulainn's ponytail almost got seared off a couple times from that asshole with the wand, but they got shit done. When the hydra was headless it finally collapsed, oozing blood and ichor. Pretty fucking gruesome and Cu Chulainn grinned before taking a step forward –

And stopping as the stranger got in front of him.

"This is mine. Do you have a problem with that?" The man asked and Cu Chulainn met cold golden eyes. He could sense the strength in them, a feeling that made him shiver and reminded him a little of his older brother. Taking a step back, he looked over the stranger.

Cu Chulainn felt more than a chill when he took him in. The stranger wore custom armor. The black leggings had leather straps and buckles and special padding. The shirt above them was black with gold lines and Cu could tell it was heavily enchanted. Over that the stranger wore a layered cloak, black with gold edging and Cu Chulainn was willing to bet it had something mystical on the back. Worse yet, the whole ensemble left the man's lower arms free and Cu Chulainn could see the Mage Crests inscribed in both tanned arms. That meant the family crest was too big and complex for just one arm and Cu Chulainn swallowed. This fucker was some serious bad news. Still, he couldn't just let this pass.

"Yes, I have a fucking problem with that! I need to pay the goddamned rent. I helped you kill that thing, give me something here," Cu Chulainn said harshly and the man's face was impassive before he slowly smiled. It wasn't a nice smile, not at all.

"Fine, dog. I'll throw you a bone." FUCK! Cu Chulainn's hands tightened around Gae Bolg at the slur. Then he had to let go to catch a bag thrown at his face. "Now get out of my sight."

"Fuck you!" Cu Chulainn snarled, burning with rage. Golden eyes trailed over his body and the man smiled again. This time it was a sweeter smile, almost impish.

"Look me up in town and I'll give you a ride. Now, go," he said before turning away and walking towards the corpse. As he walked he muttered something and a very sharp knife appeared in his hand. Cu Chulainn huffed before turning and stalking away, clutching the purse. It probably wasn't much, only a token, but it was better than nothing and he knew better than to challenge that fucker. He wasn't Setanta, not yet, and a human magus of that caliber was out of his league.

He still hated the bastard though.

* * *

 _Did I mention that I also hated him at first sight too?_

 _Oh yeah, I hated the arrogant asshole with the passion of a thousand suns. Calling me a dog… I'm a beast blood and no mistake but I hate it when people throw it in my face. He really managed to push my buttons._

 _That started to change pretty quickly though, when I got to the bar to drown my sorrows and pick up some food…_

* * *

Cu Chulainn scowled as he took a seat at the bar. The bar was cheap and nasty, which suited his mood perfectly. He tried to avoid putting his arm on the counter but it ended up sticky anyway. Slobs couldn't keep from spilling their beer.

"Well this day was a fucking bust," he muttered as one of the barmaids stared at him, already bored with his complaining. "Get me a beer, dark." She did that and easily popped the top on it before sliding it down to him. "Thanks." Cu Chulainn took a deep draught before pulling out the purse the asshole gave him. Then he opened it.

And almost spewed beer across the counter. He just barely managed to swallow before coughing.

 _The fuck?!_ Cu Chulainn stared in shock at the neatly furled notes. Maybe… they were all tenners? A quick flipping told him that was wrong though. They were all thousand notes. A quick count later and Cu Chulainn felt faint. _He gave me fourteen thousand pix!_ Holy. Shit. That was enough to pay his rent for three months! It was… pretty close to what the hydra parts would have sold for, actually. Cu Chulainn blinked and looked at the money again. Almost exactly what they were worth. Huh.

"Well… alright then," Cu Chulainn muttered as he carefully stowed the purse away and took another swig of beer. His feelings for the asshole had suddenly undergone a reversal. He was still a fucking asshole but he was also a _generous_ asshole. Cu could work with that.

Finishing his beer, he paid the barmaid before departing for better digs. If he had the money, he could drink somewhere his arms didn't stick to the bar. And maybe, just maybe he could find that dickhead and thank him. Cu Chulainn was acutely aware that he didn't really deserve that much money. Given the danger the magus had put himself in, Cu Chulainn deserved half that at best.

Cu wasn't really expecting to get lucky. But betting on where a rich, powerful magus would go, he went to the most expensive bar in the place. It was the kind of place that might kick someone like him out but Cu Chulainn walked right up to the bouncer, brazen as the day was long.

"Hey, I'm looking for a guy. Tan skin, white hair, gold eyes. Combat magus with crests on both his arms, he around?" The bouncer stared at him for a moment before pulling a face.

"Emiya is bringing his pets around?" …Fuck you! Cu's hand tightened around his spear before he forced himself to relax. "How do you know him?"

"Killed a hydra with him," Cu Chulainn said conversationally and some of the bouncer's suspicion seemed to ease.

"Huh, that'd be like him. And you get points for not asking for the owner." …Say what? Cu Chulainn tried to make sense of that and failed utterly. "Whatever, if you can pay the cover I'll let you in." Oh, right, you had to pay to get into places like this. "It's a hundred pix." That was enough for a meal but Cu didn't complain, handing over the small bill. "Emiya's in one of the booths drinking like always."

"Thanks," Cu Chulainn said before venturing inside. The place was dim and he gave his eyes a moment to adjust before glancing around. Then he whistled softly.

The expensive bar wasn't that fancy at first glance. Flooring of grey stone, chairs and tables of warm brown wood. What caught his eye, though, was the patrons and the food. The people eating here were almost all human – there were beast bloods but they mostly seemed to be hanger-ons and paid companions – and the food was damned fine. This place was almost more a restaurant than a bar and Cu Chulainn swallowed as a barmaid came out carrying a bunch of fancy drinks and some really sweet looking grilled meats. He was so hungry!

Instead of stealing the meat and getting kicked out – it almost seemed worth it – Cu began to look for his target. He found the asshole in one of the booths just like the bouncer said. He had a big plate of charcuterie and wasn't touching any of it, just staring into his booze. It looked like hard liquor and Cu Chulainn decided to join him in the booth without a by your leave.

"…" Emiya looked up from his drink with a frown and then blinked. "…When I said you could look me up for a ride, I was joking," he said before slugging back his drink. Cu wrinkled his nose at the smell. How much had this guy been drinking?

"Psh, like I'd want your hairy ass bad enough to pay the bouncer," Cu jibed before stealing some of the meat and cheese and was that jam? Holy shit look at those crackers! Emiya just watched him blankly, no indication he cared that his food was getting eaten. "I just wanted to say thank you. You didn't have to pay me that much," Cu Chulainn said as gracefully as he could. Emiya rested his cheek in one hand, blinking slowly.

"It's nothing, I'm rich." He'd kind of guessed. "And my fiancée needed hydra parts. She'd been waiting for the store to get them for so long." …HAH!

"Guess who employed me?" Cu Chulainn said cheerfully. "Go on, guess!" Emiya chuckled softly.

"Ah, so they were trying. They were going to charge twice what I paid you, it seemed like a bargain." Emiya frowned at his empty shot glass before glancing around. "What kind of drink would you like?" he asked, waiving down a waitress.

"Just beer, dark," Cu Chulainn said. He knew himself and hard liquor and his temper were not a good match. Emiya nodded as the woman, a pretty girl in a very neat uniform, came over.

"What's the best dark beer we have?" She rattled off several recommendations and Cu Chulainn picked one at random. He didn't much care as long as it had suds. "Another three Mind Erasers for me." Mind Eraser?

"Is that a magic property or are they just that strong?" he asked, interested. Emiya grunted, looking at the food blankly.

"Just that strong. Unfortunately, nothing will blot this day out of my brain." Eh? What had gone wrong? He'd gotten his hydra parts for his girl, hadn't he? "Have you ever tried to do something nice for a woman, then immediately have her accuse you of not taking her seriously and denigrating her efforts?" Emiya asked and Cu Chulainn blinked. The magus across from him dropped his head, resting his forehead in a gloved hand. "I wasn't expecting her to blow me off but I did think I would get a thank you. Instead, I was kicked out of the house… again."

"Uh… that sucks," Cu said, suddenly realizing he had a drunk, heartsick human magus on his hands. Well, half-drunk at least. "No, can't say that's ever happened to me, not twice anyway." If a woman treated him like that he'd be out the door. "Why's she your fiancée?" Maybe she had redeeming qualities? Then the drinks came and Cu sampled his beer as Emiya downed one of the shots, arranging the other two in front of him.

"Arranged marriage," Emiya said as he sat down the glass with a clink and Cu grimaced. Well, so much for that idea. "Hell of it is I think I could love her but she makes it so hard." Weird. Not that he'd ever been in a serious relationship really so what would he know? Cu kept eating the charcuterie and reflected that he seemed to be getting a free meal out of this. That made it totally worth listening to his chatter. "…Why am I telling you all this? You don't care."

"Because I'm here and you're drunk," Cu said easily and Emiya snorted softly. Cu Chulainn took a deep draught of his beer, savoring it. Ah, it was good! "Hey, try eating something," he said as Emiya downed his second shot.

"No, then I'll be conscious longer." …Well… yeah, that had been his idea… "I'll get drunk, fall under the table and my employees will haul me upstairs." Wait, employees?

"You OWN this place?" Suddenly the bouncer's little comment made sense. Emiya just gazed at him blankly and Cu Chulainn swallowed. "Holy shit, you are rich!"

"Money has never interested me," Emiya said indifferently and Cu Chulainn wanted to smack him. It was easy to say that when you had all the money in the world! "I could lose it all tomorrow and it would make no difference to me."

"Psh, I doubt that," Cu Chulainn said, unable to keep the resentment fully out of his voice. The magus lifted an eyebrow at him.

"Oh? If I was suddenly a pauper my fiancée would break up with me and I'd have to earn a living with my Mystic Codes, which I love. Losing all this would be the best thing that could ever happen to me," he said before waving at the swanky bar. "Money and position can be a cage, beast blood." Golden eyes met red and Cu Chulainn saw regret there. "Unfortunately, I was born into this cage and I can never escape."

"Hey. I'm not disagreeing, but a lot of us would give our left arms to have your problems," Cu said evenly and Emiya gazed at him for a moment before smiling thinly.

"I suppose so," he said before tossing back his third shot. Then he blinked owlishly, rubbing his head. "Ah, I'm getting there, I'm getting there…" Cu Chulainn wasn't the least bit surprised. He glanced over the charcuterie platter. He'd almost demolished it.

That brief moment of inattention cost him dearly when Emiya somehow eeled through the booth and ended up practically on his lap. Cu Chulainn tried to jerk away but then warm hands were gripping his face, intense gold eyes staring into his. Then the human kissed him and it was… hot. Incredibly, burning hot. So hot he – wait.

Why didn't he taste any booze?

Just as he was realizing something was really wrong, something sharp pricked his side and Emiya buried his face in Cu's hair, speaking in his ear. Cu Chulainn was vaguely aware that the way he was doing it ensured no one else in the room would be able to see the expression on Cu's face.

"You're either an incredibly stupid assassin or you have terrible luck. Which one is it?" Emiya breathed and Cu Chulainn swallowed, his eyes going down. The glance confirmed his worst suspicions. Emiya was holding a very sharp poniard. One jerk and it would go right into his heart.

"I'm really unlucky," Cu breathed back, holding back quiet panic. What had he stepped into? Emiya's chuckle was cold as the North winds.

"I believe you. The hydra would have been difficult to fake," he breathed and Cu Chulainn shivered as a hot tongue suddenly traced the shell of his ear. He wouldn't have thought he could get hard at a time like this but damned if he wasn't. Was being held at knife point arousing? The way Emiya's body was pressed against him didn't help at all! "Get 'drunk' and come home with me and you'll earn another ten thousand pix. Twenty if we're attacked. How does that sound?"

"Sounds great," Cu Chulainn murmured back and relaxed a bit as the prick in his side vanished. Then he was being kissed and he discovered that Emiya's lips were warm and soft, his mouth hot and eager. It was easily among the best kisses he'd ever had and Cu Chulainn enjoyed ever moment of it. Gripping the magus' shoulders – was he crazy? Setanta would say so – Cu pulled the man tightly against him.

" _Ahem!"_ The prim little cough that followed made Emiya pull away, to Cu's disappointment. The waitress was there, glaring at them. "Emiya-sama you know this kind of behavior is not allowed," she said and Cu Chulainn's lips pulled off his teeth in a silent snarl. Emiya just laughed, his cheeks a touch flushed.

"Then bring him some of my special shots. Make it an assortment," Emiya said and Cu Chulainn had a good idea what 'special' meant. Non-alcoholic. "And more food, some of that beautiful steak." Emiya smiled at him and Cu Chulainn licked his lips at before catching himself. Then Emiya lowered his voice to a slow, teasing drawn. "You'd like that, dog?" Cu almost jerked away but then a warm brown hand reached up and caught his pointed ear, giving it a gentle tug.

"I hate being called dog," Cu Chulainn grumbled, shaking his head and trying to get the hand away. Emiya chuckled, golden eyes hazed with amusement.

"Then you shouldn't wear it so obviously. You might as well have a collar." Oh, fuck you! The worst part was it was the truth, his beast blood was so obviously canine he might as well have a leash shoved up his ass. "But not all cats dislike dogs." …Huh?

"You think of yourself as a cat?" Cu Chulainn muttered as Emiya settled back into his side of the booth. The magus smiled at him, amused.

"You have no idea." That sounded interesting but they were bringing out the drinks, three shots in pretty colors. Cu Chulainn knocked back the first, a green one and tasted mind and cream but not the slightest hint of liquor. Hey, where was the smell coming from? Had Emiya spilled a real one over himself when he started drinking? Yeah, probably, that'd make sense.

It took a while but the food came out and Cu Chulainn tore through it like he was starving, which he was. Emiya kept getting drunker… so to speak… until he nearly was under the table. Then they left the club together, Cu pretending to support the magus. Emiya was incredibly good at pretending to be wasted.

It was nothing but pretense though and someone took the bait. When they were winding through a darkened alleyway – you had to use them if you wanted to get anywhere – an arrow buzzed through the air before impacting an invisible shield. Emiya was suddenly not leaning on him and weapons flashed into his hands, two swords, one light and one dark. Cu Chulainn had no time to spend on that as he flipped out his spear and used it to disrupt a bolt of fire. Fuck, they were fighting magic users!

They were just magic users, though, not magi. That was a distinction that _mattered_ when the prey was someone like Emiya. The attacks were simple and one-dimensional and would have been enough if they'd been as drunk as they seemed. But they weren't and Emiya used his own magic to delicately block and deflect before using his weapons to disembowel. Cu Chulainn held back, carefully targeting the archer on the rooftops. When he had a proper bearing he called on his spear.

" _Gae Bolg!"_ There wasn't a scream as the red spear took the sniper in the heart. The weapon flashed back and then Cu Chulainn joined the battle against the remaining assassins.

They managed to kill all but one, who beat feet before Emiya could gut him. Cu Chulainn wondered if they should chase the bastard but Emiya didn't seem to care, turning to him with an exhilarated look on his face. There was a splash of blood on his cheek, dripping off his chin.

"Well that was – MRPH!" Cu wasn't expecting the magus to jump him but that was what happened. A tongue was suddenly in his mouth as Emiya shoved him against a wall. Vaguely, Cu Chulainn recognized this. It was exactly how Setanta got after a battle, although he usually waited to get home to his wife. Those were the nights he and Diarmuid had to go for a long walk… he'd never seen it in a human though.

Then Cu didn't have time to think about it. Emiya was trying to dominate him and he wasn't going to have that from a damned human, magus or no magus! Growling he turned the tables, shoving the magus away and then pinning him to the other side of the alley. He bit Emiya's throat, eliciting a heavy groan. Hands were tearing at his clothing, working on the ties to his pants and Cu felt a sudden qualm.

"Hey, got any lube?" He muttered in Emiya's ear and the magus bit him, not gently at all.

"No, but I sometimes like pain." That was so. Fucking. Hot! "Take me right now, fuck me hard." Didn't have to tell him twice!

Buckles came off and black pants got shoved down past Emiya's knees, then his ankles. No underthings, that was convenient. Cu Chulainn didn't have any either and Emiya undid his breeches for him, letting his erection spring out. Cu tried to prepare the magus, even if it was only spit, but Emiya had no patience. He growled and jerked against him and Cu looked into wild gold eyes before mentally saying 'fuck it'. Then he was pushing his way into that hot, grasping hole, groaning at the wild squeeze on his cock. The man was so fucking tight!

"Shi… it…" Emiya growled, closing his eyes as sweat beaded on tanned skin. Cu Chulainn paused for a moment and then golden eyes opened, annoyed. "I said fuck me!"

"Demanding bastard…" Cu Chulainn growled before beginning to fuck Emiya into the wall, taking him hard. He was vaguely aware that had to hurt, his cock going in almost dry and the bricks scraping against the humans' back, but Emiya didn't complain. Instead he groaned and panted, reminding Cu of a bitch in heat. Hot, dirty and so very, very good.

Cu Chulainn didn't hold back, taking Emiya with a punishing rhythm. They kissed and it was rough, full of teeth and tongues. As they fucked in that dirty alley, surrounded by blood and gore and filth, Cu Chulainn lost himself in the magus. That tanned skin, dappled with sweat, the white hair and wild gold eyes, the unholy squeeze on his cock, became his whole world. Nothing mattered but this. Nothing.

The crazy coupling couldn't last long and Cu Chulainn surged against his partner, hearing Emiya's lustful cry just as he came. The pleasure was mind blowing, shooting through his body and numbing his brain. Cu Chulainn savored every moment, burying his face against Emiya's neck and breathing his scent. He smelled like hot metal and oil. What kind of metal? Cu Chulainn sniffed him absently. Bronze, it was bronze. Lifting his head he gazed into Emiya's face and saw him breathing heavily, his eyes dazed and tan skin still dappled with sweat. He looked fucking gorgeous and Cu Chulainn kissed him, slowly this time. The human returned the kiss, slow and almost tender.

Then Cu Chulainn was pulling away and Emiya dropped his legs, wavering on his feet before grabbing his pants and pulling them up. Cu glanced around with a frown.

"Should we do something about this?" The town guards didn't look kindly on this sort of thing. Emiya shook his head.

"I'll sort it out. You should probably get gone before they arrive though." Yeah, that was good sense for a beast blood, the authorities were always willing to pin shit on them. Emiya smiled at him, his golden eyes more relaxed than Cu had ever seen them. Cu Chulainn nodded, doing his pants back up. "Look me up at the bar next week and I might have another job for you." Oh yeah?

"I'll do that," Cu Chulainn said with a smile, feeling aches and pains now that they were done. He didn't mind though, not at all. Walking away, he savored the afterglow, feeling like he was walking on clouds. Could this day get any better?

When he'd almost got home, though, he remembered something important.

"Shit, I forgot the money!" Twenty thousand pix too! "…I can bring it up later," Cu Chulainn muttered as he went into his building. A three-story complex, he had a cheap spot in the basement. The whole place was a bit dirty but not an outright slum so he'd take it.

As he was disrobing for bed, though, Cu Chulainn heard a strange clunk when he dropped his clothing to the floor.

"…?" Picking up his vest with a frown, Cu Chulainn sorted through the pockets and pulled something out. "What the fuck?!" he whispered as he looked at the gold bar. It was marked as being worth fifty thousand pix. "Emiya you crazy bastard!" Who else could have slipped this onto him? But why? That was way more than they'd agreed! Taking a deep breath, Cu Chulainn silently blessed the mad human.

This was the best payday he'd had in his life.


End file.
